function tab(tabs,tab,tabpanels,tabpanel,classon,event){
	//tab(标签组外套，标签，内容组外套，内容，标签突出样式类名，触发事件onmouseover\onclick)
	var t=document.getElementById(tabs).getElementsByTagName(tab);
	var s=document.getElementById(tabpanels).getElementsByTagName(tabpanel);
	var len=t.length;
	var flag=0;	
	t[flag].className=classon;
	s[flag].style.display='block';
	
	for(i=0;i<len;i++){
		t[i].value = i;	
		if (event == 'onmouseover') {
			t[i].onmouseover = function(){
				changeBg(this.value)
			}
		};
		if (event == 'onclick') {
			t[i].onclick = function(){
				changeBg(this.value)
			}
		}
	}
	function changeBg(v){		
		t[flag].className='';
		s[flag].style.display='none';
		flag=v;
		t[flag].className=classon;
		s[flag].style.display='block';
	}
}